Lin Lu1, Fang Ju1, Hui Zhao1, Xuezhen Ma2. 1. Department of Oncology, The Second Affiliated Hospital of Qingdao Medical College, No. 127 South Siliu Road, Qingdao, 266042, Shandong, People's Republic of China. 2. Department of Oncology, The Second Affiliated Hospital of Qingdao Medical College, No. 127 South Siliu Road, Qingdao, 266042, Shandong, People's Republic of China. 18660229289@126.com.
Abstract
OBJECTIVES: To investigate the role of microRNAs in doxorubicin resistance of breast cancer cells. RESULTS: MicroRNA-134 was down-regulated in doxorubicin-resistant and doxorubicin-sensitive breast cancer samples and MCF-7/ADR cell lines. After transfection of miR-134 mimics, an MTT assay confirmed that the MCF-7/ADR cell proliferation was inhibited. In the presence of doxorubicin, there was inhibition of cell proliferation. Transfection of miR-134 mimics induced MCF-7/ADR cell apoptosis. The expression of ABCC1 was significantly upregulated in doxorubicin-resistant or -sensitive breast cancer tissues and MCF-7/ADR cell lines. Over-expression of miR-134 decreased the expression of ABCC1 at the protein level. CONCLUSION: MicroRNA-134 modulates resistance to doxorubicin in breast cancer cells by downregulating the expression of ABCC1 which is known to encode the multidrug resistance-associated protein 1.
OBJECTIVES: To investigate the role of microRNAs in doxorubicin resistance of breast cancer cells. RESULTS: MicroRNA-134 was down-regulated in doxorubicin-resistant and doxorubicin-sensitive breast cancer samples and MCF-7/ADR cell lines. After transfection of miR-134 mimics, an MTT assay confirmed that the MCF-7/ADR cell proliferation was inhibited. In the presence of doxorubicin, there was inhibition of cell proliferation. Transfection of miR-134 mimics induced MCF-7/ADR cell apoptosis. The expression of ABCC1 was significantly upregulated in doxorubicin-resistant or -sensitive breast cancer tissues and MCF-7/ADR cell lines. Over-expression of miR-134 decreased the expression of ABCC1 at the protein level. CONCLUSION: MicroRNA-134 modulates resistance to doxorubicin in breast cancer cells by downregulating the expression of ABCC1 which is known to encode the multidrug resistance-associated protein 1.
Entities:
Keywords:
ABCC1; Breast cancer; Doxorubicin; Doxorubicin resistance; Drug resistance; MRP1; MicroRNA-134